[Matt.S_951]

Looking for some advice on wheel sizing for an 87 951.

I want to use the car for autocross and DE's, with the focus on DE's. I will be using street tires designed for autocross, such as bfg rivals, because I don't want to swap wheels at the track

The car is currently stock. Long term plans include coilovers and about 350 HP from a Vitesse stage 3 kit. I want to make sure that whatever setup I pick will still work well at that power level and at the slightly lower ride height of the coilovers.

First question, should I go with 17 or 18 inch wheels? My inclination is 17", due to the Porsche service bulletin recommending against 18".

Next question is wheel width. I would prefer not to have to roll my fender lips. There are a couple of options that I see here:

9 f, 10 r. This seems to be a popular setup. It also seems to be about the most you can fit without rolling the fender lips.

9 f and r. Square setup, which is nice for extending tire life. Not sure if it's enough rear tire to handle my future power.

8.5" fronts also seem popular, is there a reason for this? Pairing them with 9 or 8.5 inch rears would work, but either of these options seems inferior to 9" all around.

Thanks for the help everyone.